Rotary engine.



No. 654,4l2. Patented my 24, |900. J. w. PICKEL.

'ROTARY ENGINE.

(Application led July 24, 1899.)

4 Sheets-Sheet l.

(No Model.)

me Nonms versus no. moro-uvm. msnmsmn, n. c

.No. 654,4!2. Patented July 24, i900..

, J. W. PICKEL.

ROTARY ENGINE.

(Application filed July 24, 1899.)

| @as co, woraumo.. v/Asnmcmn, n. c

wma Model.)

Patented jury 24, |900. .1. w. PICKEL. A

ROTARY ENGINE.

(Application led July 24, 1.899.)

4 Sheets-Sheet 3,

(Np Model.)

lllllllllll A N0- 654,4|2 AP t t d 1 24 |900.

w. PlcKEL. a e" e u yl noTAnY Erasme.

(Application led July 24, 1899.)-

4 Shees--Sheet 4,

` (No Model.)

was no.. PHoro-Llruov, wAsmNuwN. n. c.

NrrniD STATES'4 PATENT Orrrcn.

JOHN w. rrcn'n't, or CRYSTAL CITY, Missounr.

ROTARY ENG l N E.

SPECIFICATION forming part 0f Letters Patent NO. 654,412, dated. July24, 1900.

Application filed July 24, 1899. Serial No; 724,941. (No model.)

To @ZZ whom it may concern:

Be it known that I, JOHN W. PICKEL, a citid zen of the United States,residing at Crystal City, Jefferson county, State of Missouri, haveinvented a certain new and useful Improvement in Rotary Engines," ofwhich the following is afull, clear, and exact description, such aswillenable others -skilled in the art to which it appertains to make and usethe same, reference being had to the accompanying drawings, forming partof this specification, in which- Y Figure 1 is a vertical transversesectional View of my improved rotary engine, taken on the line 1 1 ofFig. 2. Fig. 2 is a vertical longitudinal sectional View of the same,taken on the line 2 2 of Fig. l. Fig. 3 is'a vertical transversesectional view of the same, taken on the line 3 3 of Fig. 2. Fig. 4 isin part a side elevational view and in part a longitudinal sectionalview of the same. Fig. 5 is an enlarged front elevational view of thecutoff mechanism employed in carrying out my invention. Fig. 6 is a sideelevational view of the same, partly in section. Fig. 7 is an enlargeddetail plan view of one portion of the piston and piston-head,illustrating the manner in which the packing is arranged. Fig. 8 is anenlarged vertical sectional view of the same, taken on the line S 8 ofFig. 4. Fig. 9 is an enlarged` sectional view of the same, taken on thelline 9 9 of Fig. 4, the piston being omitted. Fig. 10 is an enlargeddetail view of a portion of the mechanism employed in sliding thepiston-head, wherein I have shown a slight modification which consistsin providing a certain adjustment for the parts. Fig.`11 is a detailview showing the manner of operating the valves simultaneously; andFigs. 12 to l5 are diagrammatic views of the cut-off mechanism, showingthe manner of compensating for the difference in the throw of the camupon the movement of the fulcrum of the eccentric-rod.

This invention relates to a new and useful improvement in rotaryengines, and has for its object to provide a construction which will besimple, durable, and eficient, and one which will create the leastpossible friction between its moving parts, and at the same time insureagainst leakage of and be economical with the motive iiuid.

The essential features of this invention re-V side, first, in the novelconstruction capable of being packed in a simple and effective manner;second, in the novel means employed for controlling the movement of thepistonheads; third, in thenovel construction which renders the machineflexible; fourth, in the novel automatic'variable cutoff; fifth, in thenovel construction of the reversing valves; sixth, in the novelconstruction employed whereby the same ports and valves are utilizedwhen the engine is running in either of two directions, and, nally, theinvention consists in the novel construction, arrangement, andcombinationfof the several parts, all as will hereinafter be describedand afterward pointed out in the claims.

In the drawings, A represents the cylinder or casing,]B the piston, Cthe piston-heads,v

and D the main shaft, of my improved rotary engine. The shaft D isjournaled in the cylinder or casing and in a cap-piece E, whichcap-piece is bolted or otherwise secured to a cylinder-head F, which inturn is bolted or otherwise secured to the cylinder A. The piston B isfixed to said main shaft, and the piston-heads C, of which there arepreferably two, are designed to move radially in suitable grooves b,formed in said piston, said piston-heads being also located atdia-metrically-opposite points on said piston.

The internal diameter of the cylinder is somewhat greater than thediameter of the piston, and as said piston and cylinder are concentric,with the exception of the abutment portion a, a space is lefttherebetween, which space is traversed by the piston-heads, said spacebeing designed to receive pressure iiuid, as is well understood.

The engine illustrated in thedrawings is a reversible one and isconstructed with two ports a and a, arranged one on each side of theabutment a, said ports being controlled by suitable rotary valves a" andam', respectively, said valves d" and am being so connected that theymove simultaneously by suitable manuallyoperated cranks, links, andoperating-lever, (illustrated in dotted lines in Figs. 1 and 3 and infull lines in Fig. 11,) whereby when one valve is admitting pressure uidto the engine the other valve will be exhausting the same. This featureIOO will, however, be hereinafter more fully explained. l

a5 represents a port designed to register with both of the valves d" andam', or, more correctly speaking, registers with the passage of onevalve when in one running position, being out of registration with theother valve when in the same position, and vice versa when the engine isreversed.

G represents a cut-off valve which is practically in the form of aquadrant and is caused to rock in one direction or the other through theinstrumentality of arock-shaft g, to which it is secured, saidrock-shaft g being suitably journaled in a cap-piece g, which in turn issecured to the casin g A. The valve G, as before stated, is in the formof a quadrant and is so proportioned that its working face is an arcstruck from the center of the rock-shaft g, and obviously its seat,which I have marked g", is an arc struck from the same center. Thisspace formed between the arc g and the cap-piece g is practically amotive-fluid chest in that the mot-ive fluid is introduced thereinthrough a supply-port g', and thus said chest is kept constantly full ofmotive fluid. f

sa oc represent exhaust-ports which coperate with the valves ed and 64,said ports being formed in the casing A and communicating with theatmosphere. The valve G is provided with a port g", formed through itsarc portion, said port being located centrally between the ends of saidarc, and when said valve is rocked to and fro this port is caused toregister and pass a port a, which is in communication with the port a5.Thus it will be seen that when the valve Gpasses the port a5 a certainamount of motive fluid is admitted behind one of the piston-heads androtates the piston and its shaft, as is well understood.

The rotary valves a" and am are designed to control the admission andexhaust of motive fluid to and from the engine and are only employed inan engine built to run in either of two directions, such as isillustrated in the accompanying drawings. These valves are identical inconstruction and consist of a cylindrical body formed with a cut-outportion which when the valve is in position in its seat constitutes aport or passage, and these valves are so arranged in their seats thatthe port of one valve is in full registration with one of theabutment-ports and the port which con` ducts motive fluid to the engine,while the other of said valves is in registration with the otherabutment-port and the exhaust-passage.

` theymove simultaneously through the instrumentality of cranks a7 a8,connecting-rod a9, link al, and a lever a, which latter is pivotallymounted in a convenient place, but preferably on the casing of theengine. It will also be observed from a glanceat Figs. 3 and ll that theports of the valves and the admission and exhaust ports coperat-ingtherewith are so arrangedand proportioned .What-larger dimensions.

These valves are so connected thatA that when the operating-lever au isthrown the admission-port of one valve is positively closed before theexhaust-port of the same valve starts to open, and in the other valvethe exhaust-port will be positively closed before the admission-portstarts to open. This is a highly-desirable feature, as it enables theoperator to reverse the engine without permitting any motive fluid toescape from the motive-fluid chest through the exhaust-openings of thecasing. Another feature in the construction of these valves a" and amand their cooperating ports is that when the operating-lever au is movedto a certain position and simultaneously the two valves a" and am arerocked to a certain position communication is established between botheX- haust-ports and the interior of the cylinder of the engine throughthe instrumentality of the valve-ports and the ports a and a. Thisposition of the parts will permit air to be drawn intothe cylinderbehind one of the piston-heads and driven from the cylinder in advanceof one of the piston-heads, thus permitting the main shaft of the engineand its carried parts to rotate by momentum after the motive fluid iscut off.

I will now describe the manner in which I cause the piston-heads to moveinwardly toi ward the main shaft when they pass the abut-v ment ct andhow I prevent the great amount of friction which would otherwise beproduced if the piston-head were simply forced inwardly by the inclinedapproaches to the abutment. i y

The cylinder-head F is provided upon its outer face with a flange f,which is for a greater part of its length concentric with the main shaftand of a certain radius. This flange has also another short concentricportion, which I shall designate by f of a greater radius than thefirst-mentioned portion, and these two concentric portions are connectedby practically tangential portions, (see Fig. 1,) thus forming what Ishall term a rollertrack f. The cap-piece E, which, as before mentioned,is secured to the .cylinderhead F, is provided upon its inner face witha roller-track e, corresponding in contour with the roller-track f, butpreferably of somefroni a glance at the drawings (Fig. 2 in particular)that the abutment a is located in the lower portion of the cylinder,while the portion f of the roller-track f, as well as the correspondingportion of the roller-track e, is located at the upper portion of theengine. The reason for this is that a more direct connection can thus bemade between the roller which traverses these tracks and the pistonheadswhich saidl rollers operate.

H and I-I represent rollers designed to traverse the tracks e and f,respectively, these rollers being journaled in a rod 7L, which rod h isadjustably connected to a rod h through the medium of a turnbuckle h,said rod h being in turn pivoted to a lever t",which lever It will beobserved IOO IIO

. is in turn suitably pivoted to alug or lugs 71",

formed on the piston.

hl represents another lever, also pivoted to said lugs 71, and the freeend of this lever h7 is through the instrumentality of a link or linksh5 pivoted or connected to the inner end of the piston-head. It will beunderstood that while I have de scribed but one set of rollerconnections this mechanism is duplicated on the other side of themachine, the same being clearly illustrated in Fig. l of the drawings.The rods h are preferably guided and supported by lugs 71,6, whichextend outwardly from the edge of the piston, and thereby cause saidrods and their carried parts to rotate therewith. Inasmuch as thepiston-heads are diametrically opposite each other, it necessarilyfollows that the duplicate rollers II and H are also diametricallyopposite each other and that when one piston-head is passing over theabutment 0Ly its controlling-rollers H and H are on the upper portion ofthe roller-tracks c andfl or on the portion f' of trackf" and on thecorresponding portion of the track c, while the other piston-head notpassing the abutment has been moved outwardly from the piston andoccupies aposition in the motive-iiuid space in the cylinder, and itscontrolling-rollers H and H' are now upon the lower portions of theirtracks or the concentric portion having the shorter diameter, and thisposition of the parts will remain undistu rbed until these rollers areforced upwardly upon the portion f', at which time their controlledpiston-head will just be ready to pass the abutment a.

In order to effectually pack this rotary engine and at the same timepermit of wear of the parts, I have made the piston proper somewhatsmaller than the recess in which it is designed to be placed in thecylinder-as, for instance, I leave a clearance 1 between each end of thepiston and the heads of the cylinder. Likewise a clearance 2 is leftbetween the periphery of the piston and the bored recess 3 in thecylinder-heads. I also leave a clearance between the piston-heads andthe cylinder-heads, as at e, said clearance being filled by suitablepackingstrips 5, one each side of said piston-heads. 6 representsanother packingstrip, which is fitted into the upper edge of thepiston-head. The piston proper is provided with two continuouspacking-rings 7, which iit in circumferential grooves 8, arranged closeto its outer edges and some little distance inwardly from the rings 7,as two half-rings 9 and IO, which half-rings t in circumferentialgrooves ll and 12. These two half-rings abut or rest against aspring-actuated packing-block 13, (see Figs. 7, 8, and 9,) whichpacking-block is of a breadth equal to the thickness of the piston-headsand in perfect alinement therewith, and by virtue of its tendency tomove In order to prevent motive fluid from passing from the interior ofthe cylinder down between the piston and the casing, I have arrangedpacking-stripsle, and to prevent said Huid from passing through the slotin which the piston-head reciprocates I have arranged packings 15.

16 indicates packing-strips arranged on each side of the piston-heads,said strips being located in and near the upper end of the slot in whichsaid piston-heads slide. This construction provides for what I havetermed. the iiexibility of the engine, which flexibility consists inpermitting the piston of the en gine to revolve and at the same time beeffec tually packed regardless of whether it is perfectly true, or, tobe more explicit, if the engine-shaft is not perfectly at right anglesto the cylinder when the same is mounted or should the bearing becomeworn down after long use the engine will continue to run smoothly, forthe reason that the spaces left all around the piston `will permit saidpiston lel to the cylinder, and as the packing-rings and strips are allspring-actuated they will be either depressed or allowed to expand, asthe case may be, and tightly press against said piston and preventleakage of motive fluid between said piston and the cylinder.

to cant or occupy a position not exactly paral- I will now describe theconstruction and tric is provided with the usual opening for the passageof the shaft, and in addition thereto is a recess h', formed outwardlyfrom said opening, but opening thereinto, and in this recess is allowedto pass a key CZ, securely held in a suitable groove in said main shaft,and as this key d only takes up a small portion of the recess it will beobserved that when the shaft D is rotating in one direction-say in thedirection indicated by the arrow in Fig. 5-the shaft will immediatelyimpart motion to the eccentric; but when said shaft is rotated in theopposite direction a certain lost motion will occur, or, in other words,the shaft will rotate some distance before the key contacts with thebody of said eccentric at the other end of the recess. The reason forthis lost motion is that when the eccentric is properly set relative tothe pistonheads pressure fluid which is controlled by said eccentricwill be admitted behind one of said piston-heads at just the proper timewhen the engine is running in one direction; but when it is desired toreverse the engine it is absolutely necessary that the pistonheadstravel the distance from one side of the abutment to the other beforemotive Huid IOO IIO

ment.

is admitted-as, for instance, we will assume the engine to be at restand in the position shown in Fig. 3, where it will be noticed that theright-hand valve am is open to motive fluid and the left-hand valve cHclosed to motive fluid, and the piston-head nearest the valve is inproper position for receiving said motive fluid to start the engine inone direction; but if it is desired to start theengine in the oppositedirection and the valves d" and l60 were reversed the other piston wouldreceive motive fluid; but the eccentric would not be taken up on accountof the lost motion until the lower piston had passed the abut- Hence itis absolutely necessary that the piston-h ead be allowed to move fromits position shown in the drawings to such a position Where it will bearthe same relation to the valve 60 in such reversal as it formerly did tosaid valve 64". provided with an eccentric strap and rod I, whose looseend is slotted and coperates with a pin or stud 7'-, arranged in thefree end of a lever J, which is rigidly secured to the rockshaft g,which operates the variable cut-off valve G.

The eccentric-rod I has formed in it a slot i, and located within saidslot is a U-shaped bar K, whose upper end is pivoted to saideccentric-strap and is designed to swing thereon. This U-shaped bar,which consists practically of two parallel members connected at theirupper ends, practically fills the upper end of the slot t', while theouter faces of these parallell members are slightly tapered to such adegree that the combined width of their lower ends are somewhatvnarrower than this slot t' or are permitted to move some little distancein said slot.

L represents two parallel guide-ba rs formed on or secured to the cap E,and sliding in said guide-bars is a block INI. t l

m represents a pivoted stud or shaft having formed thereon an elongatedor working portion m, said elongated or'working portion being designedto pass between the parallel members of the U-shaped bar, said slidingblock M being caused to move upwardly and downwardly by virtue of anordinary mechanical governor, (not showm) which will be driven from theengine, it being understood, however, thatvwhen the engine is at restthis block will be at its lowest point and when the engine is startedand the speed increases the block will be moved upwardly proportionatelyto the speed attained, as will be readily understood.

As before mentioned, I employ a turnbuckle h, which cooperates with rodsh and 71,', the object of which is to minutely lengthen or shorten thedistance between the rollers H and H' and the free end of the lever h",in order to properly adjust the movement of the piston-head; butobviously this adjustment does not change the leverage, but only' allowssaidpiston-heads to move outward a given distance. While thisconstruction may This eccentric H is` be all that is desired in anaccurately-cohstructed engine, I Wish to provide for any ini accuracieswhich may occur in the construction of the roller-tracks-that is, I Wishto be' able to not have to rely entirely on the exact differentialradius of said tracks, and in order to accomplish this end I provide aconstruction as is illustrated in Fig. 10, .wherein it will be seen thatthe lever h" is cylindrical and provided with a male screw-thread, uponwhich screw-thread is placed an Unthreaded collar hg, which collar isadjusted to and held in any desired position bythread-nuts 71.9 and h1",which nuts cooperate with the threaded portion of the lever h", saidnuts being arranged one on each side of the collar hs, as shown. Thiscollar Its is designed toreceive and have pivoted thereto one end of therod h, which rod may, if desired, be bifurcated and straddle saidcollar, as is obvious.

The operation of the engine just described is as follows: When motivefluid is admitted behind the piston-heads and the piston starts torevolve, the piston-heads will be moved inwardly and outwardly at theproper time through the instrumentality ofthe rollers and tracks, and asthe speed of the engine increases the mechanical governor forces theblock M upwardly, thereby increasing the length of the distance betweensaid block and the free end of the lever J and at the same timeshortening the distance between the IOCY In Figs. 12 to l5 I have showndiagrammatic views illustrating the manner in which the lost motion ofthe inverted-U -shaped bar K is utilized to correct the point ofgreatest throw of the eccentric to accommodate the different positionsof the movable fulcrum on which its rod I rocks, whereby the motivefluid is always admitted when the pistons are in the proper position toreceive it, whether said admissions be in large or small quantities,depending upon the speed of the engine and the position of the fulcrum.

Referring now to Fig. 12 it will be seen that the eccentric will be atwhat I term one of its extreme positions, wherein the tangential line frs equivalent to the rod I, fulcrumed at m, is at right angles toa radialline drawn from s to t, the latter being the axis of rotation of themain shaft and the radius referred to being the throw of the eccentricH. In this position the eccentric-rod will be at the limit of itsstroke, and as the fulcrum is near the-free end thereof thevalve-operating rockarm .I will be at its extreme position. The

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piston-head c win be in the position Shown by the full line. Assumingthe engine to be rotating in the direction of the arrow, the pisamountof lost motion is allowed.

ton C should when the centers s, t, m, and r are in alinement be in theproper position to receive steam from the port, which proper position isindicated by the dot-and-dash line tu; but by reason of the variabilityof the fulcrum m, said fulcrum in this position of the parts being belowwhat I will term the medial center will cause the valve to admit steamwhen the piston reaches a position behind its proper position, and saidpiston will receive steam when on the linet n. Likewise when the fulcrumm is raised above the medial position the piston instead of taking steamat the proper place or on line t u, will take steam in advance of saidline or in a vposition indicated by the dotted line 1f fw.

It is obvious from the above that were the fulcrum m to occupy a medialposition the piston would receive steam at the proper place; but byreason of the adjustment of said fulcrum on either side of said medialposition the piston will receive steam in advance of or behind itsproper point. This is accounted for by reason of the circumferentialdisplacement of the point at which the attached end of the eccentric-rodis when at its extreme position, and in order to correct the tendency ofthe piston to creep either backward or forward lost motion is introducedthrough the medium of the pivoted yoke K,whereby when the fulcrum m isadjusted above or below its medial point said lost motion will permitthe piston to `lose in proportion to what it would otherwise gain werenot this lost motion provided. This is accomplished irrespective of thefact that the tangential line fr s is always at right angles to theradial line s when the rod I is at the eXtreme of its stroke.

I will state that Figs. 12 and 13 have been introduced simply -for thepurpose of illustrating the gain or loss of the piston when in theabsence of the yoke K, and Figs. 14

and 15 show how the gain or loss of the piston is compensated for byallowing the valve to rest at the end of each throw for a greater orless period of time, depending upon the position of the fulcrum m in theyoke K-that is, when the fulcrum is near the pivoted end of said yokeonly a small amount of lost motion is permitted,.while when the fulcrumis near the lower end of said yoke a greater This lost motion may besaid to permit the piston to gain on the valve in proportion to thecircumferential difference of the point s on the circle o' its travelfrom normal to abnormal.

P indicates a transverse groove or by-pass arranged across the cylinderin juxtaposition to the abutment, whose function is to relieve thepiston-head of pressure when the same is about to be retracted. Thisprevents the piston-head from binding and enables its easy and readyoperation with a minimum amount of friction.

It will be observed from a glance at the drawings and the abovedescription that by connecting the rod formed of the portions 7L h andthe turnbuckle 71. to the lever 717 at about one-third of its lengthfrom its fulcrum I onlyV need make thev difference between the radius ofthe portion fand the radius of the portion f' one-third that of thethrow of the piston-head. This is advantageous, for the reason that therollers I-I and H will not have to traverse a surface of so great avariation as would be the case if the difference between the radius ofthe cam-track were equal to the throw of the piston-heads.

In order to thoroughly lubricate the moving parts of the engine, I may,if I sodesire, introduce into the casing E, and partially ill the samewith, lubricating-oil, which when the machine is running will be forcedaround and between the moving parts, as will be readily understood.

I am aware that minor changes in the arrangement, construction, andcombination of the several parts of my device can be made andsubstituted for those herein shown and described without in the leastdeparting from the nature and principle of my invention.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is-

1. The combination with a cylinder and its shouldered head, of a pistonwhich extends beyond said shoulder in the head, peripheral packing inthe piston coperating with. said shoulder in the cylinder-head, andpacking in the cylinder-head which bears laterally against the piston;substantially as described.

2. The combination with a cylinder and cylinder-head, the latter beingprovided with a recess 3, of a piston arranged therein and carryingpacking 7, on its periphery, said cylinder-head being provided withpacking 11i to cooperate with the piston, a sliding piston- IOO headmounted in the piston, and packing 13 rings or strips which areinterposed between` said cylinder and piston to cooperate with thelatter and maintain the balance thereof; substantially as described.

4. In a rotary engine, the combinationwith a cylinderand piston, ofpiston-heads slidin gly mounted in said piston, tracks arranged on oneside only of the cylinder-rollers coperating with said tracks, and meansinterposed between said rollers and said pistonheads for operating thelatter; substantially as described.

5. The combination with a cylinder and a piston, of piston-heads movablycarried by said piston, cam-tracks arranged on one side only of thecylinder, rollers cooperating with said cam-tracks, connections betweensaid rollers and said piston-heads, and means for adjusting andregulating the movement received by the piston-heads from the rollers;substantially as described.

6. The combination with a cylinder and piston, of cam-tracks arranged onthe cylinder, a lever mounted in thepiston so as to rotate therewith, arod mounted on. said lever, a roller carried on the end of said rod forcooperating withy said cam-tracks, means for adjusting the length ofsaid rod, and a slidable piston-head which is operated by said lever;substantially as described.

7. The combination with a cylinder and its rotatable piston, ofcam-tracks arranged on the cylinder, a rock-shaft mounted in the piston,a rod mounted in guides on the piston and connected to said rock-shaft,a roller mounted in the end of the rod for coperating with saidcam-tracks, a rock-arm extending from said rock-shaft, a slidablepistonhead, and a link connection with said rockarm and saidpiston-head; substantially as described.

8. The combination With a cylinder and its head of a piston, a cap-piecearranged on said heads the cylinder, cam-tracks arranged on saidcap-piece and on said cylinder, rollers 'cooperating with said tracks,slidable pistonheads mounted in the piston, and connections between saidrollers and said pistonheads for moving the latter; substantially asdescribed.

9. In a rotary engine, the combination with a cylinder, cylinder-head,cap-piece, shaft, piston, and piston-heads, a cam-track formed on saidcap piece, a corresponding track formed on said cylinder-head, rollerswhich are arranged to coperate with said tracks,

rods upon which said rollers aremounted, means for adjusting the lengthof said rods, and levers or cranks to which the inner ends of said rodsare connected, lugs which are formed on the piston to which said leversare pivotally connected, and means for independently operating thepiston-heads from said levers; substantially as described.

' 10. The combination with a cylinder formed with an abutment, of apiston and a pistonhead, and means extending partly outside f i the'cylinder for positively withdrawing said piston-head to escape contactwith said abut'- ment; substantially as described.

11. In a rotary engine, the combination with a cylinder, its piston andpiston-heads, Said cylinder being provided with portsY for admitting andexhausting motive fluid,of an automatic variable cut-off, an eccentricloosely mounted on the main shaft of the engine, means for permittingsaid eccentric to have lost motion relative to the shaft when thedirection of rotation of the latter is reversed, an eccentric-rod foroperating the cut-off valve, and a movable fulcrum for said rod;substantially as described.

12. In a rotary engine, the combination with a cylinder, its piston andpiston-heads, said cylinder being provided with ports for admitting andexhausting motive Huid, of an automatic variable cut-off an eccentricloosely mounted on the main shaft of the engine, means for permittingsaid eccentric to have lost motion relative to the shaft when thedirection of rotation of the latter is reversed, an eccentric-rod foroperating the cut-off valve',- a movable fulcrum for said rod, and meansfor moving said fulcrum; substantially as described.

13. The combination with a cylinder, its piston and piston-head, of acut-off valve, an eccentric driven by the main shaft of the en-A gine,an eccentric-rod for vibrating said cuto valve, and a movable fulcrumfor said eccentric-rod; substantially as described.

14. The combination with a cylinder, its piston and piston-head, of acut-off valve, an eccentric driven by the main shaft of the engine, aneccentric-rod for vibrating said cutoff valve, a movable fulcrum forsaid eccentric-rod, means for permitting lost motion between the fulcrumand the eccentric-rod, when said fulcrum is in certain of its positions;substantially as described.

15. The combinationjwith a cylinder, its piston and piston-head, of acut-off valve, an eccentric driven by the main shaft of the engine, aneccentric-rod for vibrating said cutoff valve, said rod being providedwith a slot,

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ayoke pivotally arranged in said slot, and a movable fulcrum for saidrod which coperates with said yoke; substantially as described.

16. -The combination with a cylinder, its piston and piston-head, of acut-off valve, an eccentric driven by the main shaft of the engine, aneccentric-rod for vibrating said cutoff valve, guideways arranged injuxtaposition to said rod, a block slidingly mounted in said ways, ayoke pivotally mounted on said eccentric-rod and a stud carried by saidblock and coperating with said yoke to form a fulcrum therefor;substantially as described.

17. The combination with a cylinder, its piston and piston-head, of acut-off valve, an eccentric driven by the main shaft of the engine, aneccentric-rod for vibrating said cutoff valve, a movable fulcrum forsaid eccentric-rod, and means for correcting the throw of the eccentricwhen the fulcru m is adj usted; substantially as described.

In testimony whereof I hereunto affix my signature, in the presence oftwo witnesses, this 18th day of July, 1899.

JOHN WV. PICKEL.

Vitnesses:

WM. II. SCOTT, A. S. GRAY.

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